package com.bootcamp.s2_0922.ds._1004;

import javax.swing.*;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.LinkedHashMap;

/**
 * @program: myClassCode
 * @description:
 * @author: Keyu Li
 * @create: 2021-10-04 09:35
 **/

public class Demo1_HashMap {
    public static void main(String[] args) {
        HashMap map1 = new HashMap<String,Integer>(2);
        map1.put("1",1);
        LinkedHashMap<Integer, Integer> hashMap = new LinkedHashMap<>();

        System.out.println(map1.put("zs",1));

        Hashtable<Integer, Integer> hashtable = new Hashtable<>();
        hashtable.put(null,2);
    }
}
